Improved rotary cutter for planing-machine



. UNITED `STATES PATENT OFFICE.

DAVID MGKINLEY, oF PHILADELPETA, PENNsYLvAniA, AssIeNoE 'ro HIMsEnE .AND cHAELEs H. MELLoE, on sAME rnAcE.

IMPROVED ROTARY CUTTER FOR PLANlNG-MACHINE.

Specification forming part of Letters Patent No. 38,71 2, dated May 26, 1863.

t To all whom it may concern..-

Beit known that I, DAVID McKINLEY, of Philadelphia, Pennsylvania, have invented an Improved Rotary Gutterfor Planing-Machines; andI do hereby declare the following to be a full, clear, and exact description of the same, reference bein g had to the accompanying drawings, and to the letters of reference marked thereon.

My invention relates to an improvement in that class of rotary-cutters used for forming moldings, &c.; and my improvement consists ot' a cutter formed from a steel block or disk having a concavity or recess and having portions cut away, so as to leave two or three or more cutting arms and open4 spaces between the said arms, said open spaces communicating with the concavity or recess, all substantially as described hereinafter, so that the cuttingedges may be effectually cleared from the shavings, and so that said edges can bereadily sharpened.

In order to enable others to make my invention, I will now proceed to describe the manner ofl constructing the same.

0n reference tothe accompanying drawings, which form a part of this specification, Figure 1 is an exterior view of my improved cutter for planing-machines; Fig. 2, a face view of the cutter 5 Fig. 3, a sectional View; Fig. 4, an edge view of the steel disk from which the cutter is formed 5 Fig. 5, a face view of Fig. 4; Fig. 6 a transverse section of one of the arms of the cutter through the line l 2, Fig. 3.

Similar letters refer to similar parts throughout the several views.

A is therotating spindle, to which is attached the cutter for imparting the desired form to moldings and other wooden objects.

In constructing my improved cutter, I, in the rst place, take a block of steel and turn it on the outside to the form of the molding which has to be cut-as, for instance, the form represented in Fig. 4. I then turn it out on the inside, so as to form a concave recess by which the steel is made as thin as possible consistent with appropriate strength. I then cut from the outer edge of the disk to the central h ub a, two, three, or more portions, (three portions being cut away in the present instance, as indicated by the red radial lines, Fig. 5.) Ilhe piece of steel has now assumed the form represented in Figs. 1 and 2, and consists of a central hub, a, with three arms, b b b, to be converted into cutters by being beveled from the inside and reduced to sharp cutting-edges which have the desired form of the molding. The form of each arm at this stage in the construction of the cutter will be best understood by referring to the transverse section, Fig. 6, the arm being concave on the inside and convex on the outside. The conveXity of the eX- terior is, however, removed by ling or otherwise, as represented by the line m a', Fig. 6. The cutter is then secured to that portion c of the spindle which is reduced in diameter by means of a nut, B, adapted to the screwed shavings which are apt to be retained in the notches cut in the solid metal, the cuttingedges consequently becomeheated, their temper is destroyed, and frequent stoppages of thel planing-machine for the purpose of sharpening or replacing these solid cutters are unavoidable.

'Ihe concave recess in the steel disk from which my improved cutter is formed aords ample space for the dispersion of the shavings4 clear ofthe cuttin g-ed ges. The shavin gs from the cutting-edge t, Fig. 3, for instance, will naturally be propelled in the direction of the bevel of that edge, clear of the end of the spindle, its nut B, and washer d, the spaces between the cutting-arms b b b affording ample openings for the free escape of the shavin gs.

Another advantage of the concavity of the steel disk from which my improved cutter is formed is the facility which the said recess and open space between the cutting-arms aifords for sharpenin g the cuttin g-ed ges, as an oil-stone of limited dimensions, held in the position indicated by the arrow, Fig. 3, can be readily applied to the cutting-edges.

A further advantage of the concave recess in the steel disk is the reduction of the metal in thickness, :t beveled edge of thin steel making a much cleaner cut tha-n a beveled edge of thick steel, even though the angle of the edge be the same in both.

I claim as my invention and desire to secure by Letters Patent- The rotary cutter formed from a steel block or disk having ai coneztvity or recess and hevin g portions cut away so as to leave two, three, or more cutting-arms and open spaces between the said arms b, the said spaces communicating with the recess, all substantially as set forth, for the purpose specified.

In testimony whereof I have signed my name to this specicetion in the presence of two subscribing witnesses.

DAV. MCKIN LEY.

Witnesses:

CHARLES E. FOSTER, J onN WHITE. 

